INFORM May 2026

AOCS METHODS INFORM 19

methods. AOCS has been working with industry partners to improve the existing AOCS HS-GC-FID method for determining hexane residues. At the same time, the German Society for Fat Science (DGF) has established the Joint Committee for the Analysis of Fats, Oils, Fatty Products, Related Products and Raw Materials (GA Fett) to develop a method based on HS-GC MS, which is already used routinely by SGS laboratories. AOCS is considering cooperative validation efforts with ISO for the DGF method. Such collaboration could play an important role in establishing the next generation of harmonized analytical tools for monitoring hexane residues. COULD HEXANE BE REPLACED? While improvements in analytical methods address one part of the hexane discussion, another question often arises alongside regulatory reassessment: Could hexane itself eventually be replaced? The search for alternative extraction solvents is not new. For several decades, researchers have explored a variety of potential substitutes, motivated by environmental considerations, worker safety, and evolving regulatory expectations. Among the alternatives studied are ethanol, isopropanol, supercritical carbon dioxide, aqueous enzymatic extraction, and more recently bio based solvents such as 2-methyloxolane.

Some of these technologies have shown promising results in pilot studies or niche applications. However, none has yet matched the combination of characteristics that made hexane so successful in the first place. Hexane offers high selectivity for non-polar lipids, efficient solvent recovery due to its relatively low boiling point, an established industrial infrastructure, and a low cost. No alternative solvent replicates all of these characteristics simultaneously. In many cases, alternative solvents introduce new challenges. Some require higher energy input for solvent recovery, while others extract a broader range of compounds that complicate downstream refining. Implementing these alternatives may also require significant modifications to existing extraction equipment, making a large-scale transition both technically and economically complex. For these reasons, although solvent substitution continues to be an important area of research, the transition away from hexane—if it occurs—will likely be gradual. The pace of change will depend not only on technological advances but also on regulatory developments, economic considerations, and industry investment in new processing technologies. WHAT COMES NEXT As the reassessment of hexane moves forward, the conversation is shifting from discussions of historical use to

questions of data quality and scientific evidence. Regulators will rely heavily on analytical measurements to evaluate exposure and assess potential risks. Consequently, the reliability and comparability of analytical datasets are central concerns. This places new emphasis on the development of harmonized analytical methods capable of producing consistent results across laboratories and geographic regions. Achieving this goal will require collaboration among industry stakeholders, analytical laboratories, instrument manufacturers, and standardization bodies such as AOCS, ISO, and DGF. Through coordinated validation studies and continued advances in analytical technology, the industry has an opportunity to ensure that the scientific foundation supporting regulatory decisions is robust, transparent, and internationally comparable. In this way, the evolving discussion around hexane may ultimately strengthen not only regulatory oversight but also the analytical tools used to monitor solvent residues in the global food supply.

Xin Wu is a manager in Technical Services at AOCS. She can be contacted at xwu@aocs.org.